In a skillet over medium heat, add a small amount of oil, bell peppers and onion, stir and cook until softened
Add the beans, reduce heat to low and cook gently for 5 minutes.
In bowl combine mangos, lime juice, cilantro, and avocado, stir and keep cold.
Evenly divide the warm bean mixture in the middle of each tortilla, then evenly divide the cold mango mixture on top of each.
Roll the tortillas up and serve.